Automatic declutching and cut-off control devices for spring winding machines



Oct. 14, 1958 J. E. HECKETHORN 2,355,974

. AUTOMATIC DEQLUTCHINGYAND CUT-OFF CONTROL DEVICES FOR SPRING WINDING MACHINES Filed Jan. 28, 1957 3 Sheets-Sheet 1 Fig. I

INVENTOR.

F I9. 2 ...BY

Wafi

ATTORNEY Oct. 14, 1958 J. E. HECKETHORN AUTQMATIC DECLUTCHING AND CUT-OFF CONTROL .DEVICES FOR SPRING WINDING MACHINES 3 Sheets-Sheet 2 Filed Jan. 28, 1957 ATTORNEY Oct. 14, 1958 J. E. HECKETHORN 2,855,974

AUTOMATIC nscw'rcnmc AND CUT-OFF CONTROL DEVICES FOR SPRING WINDING MACHINES Filed Jan. 28, 1957 v 3 Sheets-Sheet 5 Fig. 5

INVENTOR. Jam [Afr/M76 02 ATTORNEY AUTOMATIC DECLUTCHING AND CUT-OFF CONTROL DEVICES FOR SPRING WIND- ING MACS John E. Hecltethorn, Denver, Colo., assignor to Heckethorn Manufacturing & Supply Company, Littleton, (1010., a corporation of Colorado Application January 28, 1957, Serial No. 636,656

, 6 Claims. (Cl. 15365) This invention reltaes to a spring winding machine, and more particularly to an automatic control device for spring winding machines. Conventional spring winding machines are so arranged that an operator feeds a continuous wire into the machine; starts the machine to wind the wire in a continuous spiral length; stops the machine when the desired length has been wound; and then operates a cutofi device to cut the wire at the terminus of the wound spring.

The principal object of this invention is to provide an automatic control device which can be easily and economically applied to a spring winding machine of the type described above and which can be preset to automatically stop the machine when a spring of preset length has been wound; cut the wire; and restart the machine on a second similar spring without manual attention; and to so construct the control device that it will not interfere with manual operation and control of the machine when desired.

Other objects and advantages reside in the detail construction of the invention, which is designed for simplicity, economy, and efficiency. These will become more apparent from the following description.

In the following detailed description of the invention, reference is had to the accompanying drawing which forms a part hereof. Like numerals refer to like parts in all views of the drawing and throughout the description.

In the drawing:

Fig. l is a front view of a conventional spring winding machine, illustrating the parts and elements to which the improved control device is applied;

Fig. 2 is a plan view of the machine of Fig. 1 with the improved control device in place thereon;

Fig. 3 is an enlarged rear view of the spring winding machine with the control device in place thereon and with a V-belt drive sheave removed therefrom to show the mechanism therebehind;

Fig. 4 is a similar rear view with a ratchet lever removed therefrom and with a cam disc of the control device broken away to illustrate the structure therebehind;

Fig. 5 is a sectional view looking downwardly on the line 55, Fig. 3; and

Fig. 6 is a detail, face view of a cam disc employed in the improved attachment device.

The usual elements of a conventional spring winding machine are herein designated by numeral as follows: front frame plate 10, rear frame plate 11, -base plate 12, wire table 13, wire straightening rolls 14, roll tension knob 15, clutch lockout shaft 16, manual clutch operating handle 32, diameter control knob 17, pitch control knob 18, upper roll shaft 19, lower roll shaft 20, drive shaft 21, cutoff shaft 22, winding mandrel 23, mandrel shear edge 31, upper wire roller 24, lower wire roller 25, diameter control blade 26, cutoff blade 27, manual cutoff handle 28, V-belt drive sheave 29, and pitch control blade In the conventional machine, the diameter of the spring Patented Oct. 14, 1958 to be wound is set by means of the diameter control knob 17, the pitch of the spring to be wound is preset by means of the pitch control knob 18. The wire is fed through the straightening rolls 14 on the wire table 13 and between the upper and lower wire rollers 24 and 25. Power is supplied to the sheave 29 and drive shaft 21 in any desired manner so as to cause the rollers 24 and 25 to force the wire against the diameter control blade 26 and around the stationary mandrel 23 to form a continuous wire spring, the pitch of which is controlled by presetting the pitch control blade 30 through the medium of the pitch control knob 18. When the desired length of spring has been produced, the machine is stopped by manual actuation of the clutch handle 32 and the cutoff handle 28 is then manually operated to swing the cutoff blade 27 against the wire to shear the latter against the shearing edge 31 on the mandrel 23 to cut the wire so as to release a spring of the desired length.

This improved control device is designed to allow the machine to wind a spring of a predetermined number of turns; stop the machine at the termination of the spring; actuate the cutoff shaft 22 to cause the cutoff blade 27 to shear the wire and release the wound spring; and then to return the clutch shaft 16 to the operating position to restart the machine to produce a second similar spring.

In applying this invention, a conventional releasable, directional clutch 33 is applied to the rear extremity of the drive shaft 21 and the housing of the clutch 33 is extended rearwardly to form a hub 34 upon which an eccentric35 is formed. The V-belt sheave 29 is concentrically mounted relative to the shaft 21 upon the rear face of the eccentric 35 by means of suitable attachment screws 36 so that the power is transmitted through the clutch to the drive shaft 21.

A bearing pedestal 37 is mounted on the rear frame plate 11 by means of suitable attachment screws 38, or in any other desired manner, so as to support a stub shaft 39 thereon. A circular cam disc 40 is rotata'oly mounted on suitable bearings 41 on the stub shaft 39. A directional clutch drum 42 is secured on each face of the disc 40 about the bearings 41.

The directional clutch drums 42 are of any of the conventional varieties provided with clutch rollers 43 which engage the pedestal 37 to prevent reverse rotation of the cam disc 40 and with clutch rollers 44, which are engaged by a ratchet hub 45 to impart forward rotation to the cam disc 40. The ratchet hub 45 is mounted on suitable anti-friction bearings 46 on the stub shaft 39 and a ratchet lever 47 is mounted on the ratchet hub 45 by means of suitable mounting screws 48.

The ratchet lever 47 carries a cam follower roller 49 positioned to be resiliently urged into the eccentric path of the rotating eccentric 35 by means of a follower spring 82 tensioned between the lever 47 and a spring stud 83 on the back plate 11. Thus, it can be seen that the sheave 29 will rotate the eccentric 35 and the latter will, due to its eccentricity, ride against the follower roller 49 during each revolution to cause the latter to oscillate. This oscillation is imparted through the ratchet lever 47, the hub 45, the clutch rollers 44, to the circular cam disc 40, to cause the latter to move forwardly, that is, clockwise in Fig. 3, with an intermittent movement.

The degree of rotation at each oscillation can be regu- I 3 stop boss 55 which contacts and rests upon the stop arm 54 to limit the downward movement of the operating arm.

Thus, it can be seen that the at rest position of the roller 49 can be adjusted so as to take advantage of all or any part of the eccentricity of the eccentric 35 so that the length of the stroke made by the ratchet lever 47 can be accurately preset to control the degree of movement imparted to the cam disc 40 at each revolution of the eccentric 35.

The c'am' disc 40 is provided with one or more cutoff earns 56. The cams 56 are secured to the rear face of the cam disc by means of suitable attachment screws 57 so as to project radially from the periphery of the disc. The number of cutoff cams depends upon the lengths of the springs to be wound. More cams are employed for relatively short springs than for the longer springs. As illustrated, four of the cutoff cams are employed.

A cutoff actuating lever 58 is mounted on the rear extremity of the cutoff shaft 22 and acts to maintain a cam-follower roller 59 in the circular path of rotation of the cutoff cams 56. The cam-follower roller 59 is constantly and resiliently urged toward the axis of the cam disc by means of a tension spring 60 extending from a fixed spring stud 61 on the base plate 12 to a spring arm 62 formed on or attached to the cutoff actuating lever 58. v

A plurality of arcuate clutch-operating dogs 63 are mounted in a circular dog-retaining groove 79 in the front face of the cam disc by means of suitable attachment screws 64, there being one clutch-operating dog 63 positioned in the space intermediate each of the cutoff cams 56. A second bearing pedestal 65 is mounted on the rear frame plate 11 and pivotally supports a camfollower arm 66. The arm 66 is formed with a spring car 76 and carries a cam-follower roller 67 in the circular path of rotation of the clutch-operating dogs 63.

A clutch-engaging lever 68 is also independently and rotatably mounted on the pedestal 65 and terminates in a clutch-engaging hook 69 positioned to be swung into engagement with a stop notch 70 on the clutch 33 to disengage or release the clutch. Conventional, releasable, directional clutches, such as the clutch 33, are provided with such stop notches with which a stationary member may be engaged to completely release the clutch. The clutch-engaging lever 68 is extended oppositely from the bearing pedestal 65 to form a spring arm portion 73 thereon. A tension spring 84 is tensioned between the spring ear 76 and the spring arm portion 73 to constantly and resiliently urge the latter portion against the head of a stop screw 75 in the cam-follower arm 66.

The cam-follower arm 66 and the roller 67 are constantly and resiliently urged inwardly toward the axis of the cam disc 40, and into the path of the dogs 63, by means of a tension spring 1, tensioncd between the spring car 76 and a spring Stud 72 on the rear frame plate 11. The inward movement of the cam-follower arm is communicated to the clutch-engaging lever 68 to lift the hook 69 from engagement with the stop notch 70 by the stop screw 75 and the spring arm portion 73.

A manual clutch-control lever 74 is fixedly mounted on the cam follower arm 66 by means of the stop screw 75 or in any other desired manner and extends sidewardly and downwardly to a position adjacent the clutch lockout shaft 16. A clutch lockout lever 77 is mounted on and extends radially from the clutch lockout shaft 16 and is positioned to engage a roller or lug 73 on the extremity of the clutch control lever 74 when the shaft 16 is manually rotated countcr-clockwise in Fig. 3 or clockwise in Fig. 1.

Rotation can be manually imparted to the shaft 6 at any time by means of the clutch lockout handle 32 which projects upwardly to a conveniently reached location above the machine. The shaft 16 is retained in the lockout position by means of a tension spring 80 connected to a spring lever 81 at the front of the machine and arranged to swing back and forth over the dead center point of the spring lever 81. Thus, it can be seen that the hook can be manually urged to swing the hook 69 into position to engage the stop notch 70 and lock the clutch 33 in the disengaged position by means of the clutch handie 32.

It is believed that the construction of the invention can be best understood by following through a sequence of operations. Let us assume that the clutch lockout handle is in the engaged position so that the clutch lockout lever has been swung upwardly by the spring 71 to disengage the clutch hook so that power is being transmitted through the clutch 33 to the spring winding mechanism to form the spring. The winding continues and the cam disc rotates intermittently until one of the dogs 63 contacts the cam follower roller 67 and forces the latter away from the axis of the cam disc to tension the spring 71 and bring the hook 69 into resilient contact with the clutch 33 so that the stop notch 70 will abut ther'eagainst and disengage the clutch 33 to stop the winding mechanism. The eccentric 35 and the cam disc 40 continue to rotate to bring a cutoff cam 56 into contact with the follower roller 59 to rotate the cutoff shaft 22 to cause the cutoff blade 27 to sever the wire at the termination of the completed spring. The cam disc 40 continues to rotate so that the dog 63 that is engaging the roller 67 will move out of engagement therewith to release the clutch hook 69 and allow the clutch 33 to reengage to supply power to the drive shaft 21 to actuate the wind ing mechanism for winding a second spring. At the conclusion of the second spring the next successive dog 63 will engage the roller 67 and the above described stopcutoff-start sequence will be repeated.

The lengths of the springs being wound can be adjusted during operation by rotating the stroke adjusting knob to cause the stop arm 54 to vary the degree of contact between the eccentric 35 so as to adjust the R. P. M. of the cam disc. Should longer or shorter springs be desired than can be provided by the above adjustment, the number of dogs 63 and the number of cutoff cams 56 on the cam disc may be varied.

The winding can be manually stopped at any time by actuation of the lockout handle 79 and the wire may be manually cut when desired by actuation of the manual cutoff handle 28.

While a specific form of the improvement has been described and illustrated herein, it is to be understood that the same may be varied within the scope of the appended claims, without departing from the spirit of the invention.

Having thus described the invention, what is claimed and desired secured by Letters Patent is:

1. A control device for a wire spring winding machine of the type having a drive shaft for actuating the spring winding mechanism and a cutoff shaft for actuating a cutoff blade for severing the wire at the termination of the winding, comprising: a rotary power-driven element; a clutch arranged to transmit power from said powerdriven element to said drive shaft; an eccentric rotated by said power-driven element; a rotary cam disc; a ratchet lever mounted concentrically with said cam disc and positioned to be actuated by the eccentricity of said eccentric; means for transmitting motion from said ratchet lever to said cam disc to intermittently rotate the latter; a cutoff cam projecting from said cam disc; a cutoff actuating lever mounted on said cutoff shaft in the path of said cutoff cam to be actuated by the latter when said cam disc reaches a predetermined position; means for disengaging said clutch prior to actuation of said cutoff shaft; a plurality of said cutoff cams on said cam disc; a clutchoperating-dog mounted on said cam disc adjacent to each of said cutoff cams; means operable by said clutch-operating-dogs for releasing said clutch to stop the winding machine prior to actuation of said cutoff shaft; and an adjustable stop device positioned in the path of movement of said ratchet lever for limiting its degree of movement toward said eccentric.

2. A control device for a wire spring winding machine of the type having a drive shaft for actuating the spring winding mechanism and a cutofi shaft for actuating a cutoff blade for severing the wire at the termination of the winding, comprising: a rotary power-driven element; a clutch arranged to transmit power from said power-driven element to said drive shaft; an eccentric rotated by said power-driven element; a rotary cam disc; a ratchet lever mounted concentrically with said cam disc and positioned to be actuated by the eccentricity of said eccentric; means for transmitting motion from said ratchet lever to said cam disc to intermittently rotate the latter; a cutofi cam projecting from said cam disc; a cutofl actuating lever mounted on said cutoff shaft in the path of said cutoff cam to be actuated by the latter when said cam disc reaches a predetermined position; means for disengaging said clutch prior to actuation of said cutoff shaft; a plurality of said cutoff cams on said cam disc; a clutchoperating-dog mounted on said cam disc adjacent to each of said cutoiI cams; a cam-follower arm mounted on said machine; a cam-follower roller mounted on said arm in the path of rotation of said dogs to be contacted by the latter; and clutch-actuating means operable in consequence of movement of said cam-follower arm for releasing said clutch.

3. A control device as described in claim 2 in which the clutch actuating means comprises: a clutch-engaging lever mounted independently and concentrically of said camfollower arm; a clutch-engaging hook formed on said clutch-engaging lever and positioned to engage and release said clutch; and means for transmitting movement 6 from said cam-follower arm to said clutch-engaging lever.

4. A control device as described in claim 3 in which the means for transmitting movement comprises: a fixed abutment on said cam-follower arm positioned to engage said clutch-engaging lever to urge the latter away from said clutch; and resilient means positioned between said camfollower arm and said clutch-engaging lever to resiliently urge said clutch-engaging lever toward engagement with said clutch.

5. A control device as described in claim 4 having manually operated means connected with said cam-follower arm for actuating the latter independently of said dogs.

6. A control device as described in claim 5 in which the manually-operated means comprises: a clutch-lockout shaft rotatably supported in said machine; a clutchlockout lever mounted on and projecting from said shaft; and a clutch control lever secured to said cam-follower arm and extending into the path of said clutch-lockout lever to transmit movement from said clutch-lockout shaft to said lever to cause said hook to engage and re lease said clutch.

References Cited in the file of this patent UNITED STATES PATENTS 

